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arXiv · 0710.0310

Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions

J. W. Holt·G. E. Brown·T. T. S. Kuo·J. D. Holt·R. Machleidt
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Abstract

We present shell model calculations for the beta-decay of the 14C ground state to the 14N ground state, treating the states of the A=14 multiplet as two 0p holes in an 16O core. We employ low-momentum nucleon-nucleon (NN) interactions derived from the realistic Bonn-B potential and find that the Gamow-Teller matrix element is too large to describe the known lifetime. By using a modified version of this potential that incorporates the effects of Brown-Rho scaling medium modifications, we find that the GT matrix element vanishes for a nuclear density around 85% that of nuclear matter. We find that the splitting between the (J,T)=(1+,0) and (J,T)=(0+,1) states in 14N is improved using the medium-modified Bonn-B potential and that the transition strengths from excited states of 14C to the 14N ground state are compatible with recent experiments.

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J. W. Holt, G. E. Brown, T. T. S. Kuo, J. D. Holt, R. Machleidt. 2008-02-06. Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions. https://doi.org/10.1103/physrevlett.100.062501

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